| 摘要 |
<p>An injection device for use in injecting a fluid into a target location includes a housing defining an inlet for communicating with a source of injection fluid, an outlet for communicating with a target injection location, and a separate reference port for communicating with a reference pressure source. The device also includes first and second valve members mounted within the housing, wherein the second valve member defines a flow path therethrough to facilitate fluid communication between the inlet and outlet of the housing. A sealing arrangement is provided between the second valve member and the housing such that fluid pressure at the housing inlet and housing reference port apply a force on the second valve member to cause said second valve member to move relative to the first valve member and vary flow between the inlet and the outlet.</p> |
